Means penis and is derived from the term pen15 which is used by baddies in years five, six and seven as a way to make themselves look like immature wankers. Can be used with other words such as mastie and reckie to make people laugh while making fun of the kind of kids who would actually be in the pen15 club.
Vinnie popped a reckie as hard as a diamond then chucked a mastie until his Pen-Fift felt like it was made of clay
by Rough_Bastard February 28, 2010